.all{ 
  /*background-color:#F5E2EC;*/ /*背景颜色*/
  background-image: url(assets/image/background.png); /*背景图片*/
  background-size: cover;
  border-radius: 4px;
  margin: 0 auto;
}
.useless1{
  opacity:0; /*按钮透明化*/
}
.home {
    text-align: center;
    margin-top: 35%;
  }
  
  .home button {
    position: relative;
    margin-right: 40px;
    margin-left: 40px;
    width: 140px;
    height: 90px;
    background-color: rgba(190, 154, 154, 0.5);
    border: none;
    padding: 5px 10px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 30px;
    /*opacity:0.6;*/
  }
  
  .home button:hover {
    color: #af6967;
    background-color: #c79bad;
  }

  .useless2{
    margin-top: 15%;
    opacity:0; /*按钮完全透明化*/
  }
  